ucar.visad
Class VisADMath

java.lang.Object
  ucar.visad.VisADMath

public final class VisADMath
extends Object

Utility class: provides support for mathematical operations on VisAD data objects.

Author:

Steven R. Emmerson $Id: VisADMath.java,v 1.15 2005/05/13 18:34:06 jeffmc Exp $

Nested Class Summary

protected static class

VisADMath.Index Provides support for indexing sample points.

Method Summary

static Data	add(Data data1, Data data2) Adds two data objects together.
static FlatField	curveIntegralOfGradient(Field field) Returns the indefinite curve integral of a Field, which is assumed to be the gradient of a function.
static Data	divide(Data data1, Data data2) Divides one data object by another.
static Data	exp(Data data) Exponentiates a data object.
static FlatField	fromReference(FunctionType type, FlatField data) Transforms a FlatField object from a reference CoordinateSystem.
static Data	fromReference(MathType type, Data data) Transforms a data object from a reference CoordinateSystem.
static RealTuple	fromReference(RealTupleType type, RealTuple data) Transforms a RealTuple object from a reference CoordinateSystem.
static IrregularSet	fromReference(SetType type, SampledSet data) Transforms a SampledSet object from a reference CoordinateSystem.
static Data	invert(Data data) Inverts a data object by forming the reciprocal.
static Data	log(Data data) Takes the natural logarithm of a data object.
static void	main(String[] args) Tests this class.
static Data	multiply(Data data1, Data data2) Multiplies two data objects together.
static Data	negate(Data data) Negates a data object.
static FlatField	newFlatField(SampledSet set) Creates a FlatField from a SampledSet.
static FlatField	newFlatField(SampledSet set, MathType rangeType, CoordinateSystem rangeCoordinateSystem) Creates a FlatField from a SampledSet, a MathType for the range, and a CoordinateSystem for the range.
static FlatField	newFlatField(SampledSet domain, SampledSet range) Creates a FlatField from two SampledSet-s.
static FlatField	newFlatField(SampledSet domain, SampledSet range, MathType rangeType, CoordinateSystem rangeCoordinateSystem) Creates a FlatField from a domain SampledSet, a range SampledSet, and a CoordinateSystem for the range.
static Data	pow(Data base, Data exponent) Raises one data object to the power of another.
static Data	subtract(Data data1, Data data2) Subtracts one data object from another.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

negate

public static Data negate(Data data)
                   throws VisADException,
                          RemoteException

Negates a data object.

Parameters:

data - The data object to be negated.

Returns:

The result of negating the data object.

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

invert

public static Data invert(Data data)
                   throws VisADException,
                          RemoteException

Inverts a data object by forming the reciprocal.

Parameters:

data - The data object to be inverted.

Returns:

The result of inverting the data object.

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

exp

public static Data exp(Data data)
                throws VisADException,
                       RemoteException

Exponentiates a data object.

Parameters:

data - The data object to be exponentiated.

Returns:

The result of exponentiating the data object.

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

log

public static Data log(Data data)
                throws VisADException,
                       RemoteException

Takes the natural logarithm of a data object.

Parameters:

data - The data object to have the natural logarithm taken.

Returns:

The result of taking the natural logarithm of the data object.

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

add

public static Data add(Data data1,
                       Data data2)
                throws UnimplementedException,
                       TypeException,
                       ArithmeticException,
                       VisADException,
                       RemoteException

Adds two data objects together. The computational modes are Data.WEIGHTED_AVERAGE and Data.NO_ERRORS.

Parameters:

data1 - The first data object.

data2 - The second data object.

Returns:

The result of adding the two data objects together.

Throws:

UnimplementedException - Operation not yet implemented.

TypeException - MathTypes are incompatible.

ArithmeticException - Invalid operation between types.

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

subtract

public static Data subtract(Data data1,
                            Data data2)
                     throws UnimplementedException,
                            TypeException,
                            ArithmeticException,
                            VisADException,
                            RemoteException

Subtracts one data object from another.

Parameters:

data1 - The first data object.

data2 - The second data object.

Returns:

The result of subtracting the second data object from the first data object.

Throws:

UnimplementedException - Operation not yet implemented.

TypeException - MathTypes are incompatible.

ArithmeticException - Invalid operation between types.

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

multiply

public static Data multiply(Data data1,
                            Data data2)
                     throws UnimplementedException,
                            TypeException,
                            ArithmeticException,
                            VisADException,
                            RemoteException

Multiplies two data objects together. The computational modes are Data.WEIGHTED_AVERAGE and Data.NO_ERRORS.

Parameters:

data1 - The first data object.

data2 - The second data object.

Returns:

The result of multiplying the first data object by the second data object.

Throws:

UnimplementedException - Operation not yet implemented.

TypeException - MathTypes are incompatible.

ArithmeticException - Invalid operation between types.

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

divide

public static Data divide(Data data1,
                          Data data2)
                   throws UnimplementedException,
                          TypeException,
                          ArithmeticException,
                          VisADException,
                          RemoteException

Divides one data object by another.

Parameters:

data1 - The first data object.

data2 - The second data object.

Returns:

The result of dividing the first data object by the second data object.

Throws:

UnimplementedException - Operation not yet implemented.

TypeException - MathTypes are incompatible.

ArithmeticException - Invalid operation between types.

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

pow

public static Data pow(Data base,
                       Data exponent)
                throws UnimplementedException,
                       TypeException,
                       ArithmeticException,
                       VisADException,
                       RemoteException

Raises one data object to the power of another.

Parameters:

base - The data object to be raised by a power.

exponent - The exponent by which to raise the base.

Returns:

The result of raising the base data object by the power of the exponent data object.

Throws:

UnimplementedException - Operation not yet implemented.

TypeException - MathTypes are incompatible.

ArithmeticException - Invalid operation between types.

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

fromReference

public static Data fromReference(MathType type,
                                 Data data)
                          throws TypeException,
                                 VisADException,
                                 RemoteException

Transforms a data object from a reference CoordinateSystem. When the data object is a FlatField, then the transformation applies to its range and not its domain.

Parameters:

type - The VisAD MathType of the returned data object. It shall be a RealTupleType, SetType, or FunctionType and shall have a CoordinateSystem, which shall be used in the transformation.

data - The data object to be transformed. The object shall be a Real, RealTuple, SampledSet, or FlatField.

Returns:

The transformed data object. Its VisAD MathType shall be type.

Throws:

TypeException - Data object has illegal type.

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

fromReference

public static RealTuple fromReference(RealTupleType type,
                                      RealTuple data)
                               throws VisADException,
                                      RemoteException

Transforms a RealTuple object from a reference CoordinateSystem.

Parameters:

type - The MathType of the returned data object. It shall have a CoordinateSystem, which shall be used in the transformation.

data - The RealTuple object to be transformed.

Returns:

The transformed data object.

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

fromReference

public static IrregularSet fromReference(SetType type,
                                         SampledSet data)
                                  throws VisADException

Transforms a SampledSet object from a reference CoordinateSystem.

Parameters:

type - The MathType of the returned data object.It shall have a CoordinateSystem, which shall be used in the transformation.

data - The SampledSet object to be transformed.

Returns:

The transformed data object.

Throws:

VisADException - Couldn't create necessary VisAD object.

fromReference

public static FlatField fromReference(FunctionType type,
                                      FlatField data)
                               throws VisADException,
                                      RemoteException

Transforms a FlatField object from a reference CoordinateSystem.

Parameters:

type - The MathType of the returned data object.It shall have a CoordinateSystem, which shall be used in the transformation.

data - The data object to be transformed.

Returns:

The transformed data object.

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

curveIntegralOfGradient

public static FlatField curveIntegralOfGradient(Field field)
                                         throws FieldException,
                                                VisADException,
                                                RemoteException

Returns the indefinite curve integral of a Field, which is assumed to be the gradient of a function. This method can handle any Field whose range is one of the following:

   Scalar derivative       dy/dx

   RealTuple of partial
   derivatives             (du/dx, du/dy, ...)

   Tuple of RealTuple-s
   of partial derivatives
   (one set of partial
   derivatives for each
   component of the
   resulting FlatField)    ((du/dx, du/dy, ...), (dv/dx, dv/dy, ...), ...)
 

The domain points of the returned FlatField will be the same as the Field's. The type of the range of the returned FlatField will depend on the type of the range of the Field. The value of the range at the first domain point of the returned FlatField shall be arbitrarily set to (possibly vector) zero.

Parameters:

field - The Field whose indefinite curve integral is to be computed.

Returns:

The indefinite curve integral of the Field.

Throws:

FieldException - The Field has a non-flat range or range dimension of Field != domain dimension of Field.

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

newFlatField

public static FlatField newFlatField(SampledSet set)
                              throws VisADException,
                                     RemoteException

Creates a FlatField from a SampledSet. This method should, perhaps, become a method in visad.Set or a constructor in FlatField.

Parameters:

set - The SampledSet.

Returns:

The SampledSet promoted to a FlatField. The MathType of the domain and range will be the RealTupleType of the set (i.e. ((SetType)set.getType()).getDomain(). The CoordinateSystem of the range will be that of the set (i.e. set.getCoordinateSystem()).

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

newFlatField

public static FlatField newFlatField(SampledSet domain,
                                     SampledSet range)
                              throws VisADException,
                                     RemoteException

Creates a FlatField from two SampledSet-s. This method should, perhaps, become a method in visad.Set or a constructor in FlatField.

Parameters:

domain - The domain of the FlatField.

range - The range of the FlatField.

Returns:

The SampledSet promoted to a FlatField. The MathType of the domain and range will be the RealTupleType of the set (i.e. ((SetType)set.getType()).getDomain(). The CoordinateSystem of the range will be that of the set (i.e. set.getCoordinateSystem()).

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

newFlatField

public static FlatField newFlatField(SampledSet set,
                                     MathType rangeType,
                                     CoordinateSystem rangeCoordinateSystem)
                              throws VisADException,
                                     RemoteException

Creates a FlatField from a SampledSet, a MathType for the range, and a CoordinateSystem for the range. This method should, perhaps, become a method in visad.Set or a constructor in FlatField.

Parameters:

set - The SampledSet.

rangeType - The MathType of the range for the returned FlatField.

rangeCoordinateSystem - The CoordinateSystem for the range of the returned FlatField. May be null.

Returns:

The SampledSet promoted to a FlatField. The MathType of the domain will be the RealTupleType of the set (i.e. ((SetType)set.getType()).getDomain().

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

newFlatField

public static FlatField newFlatField(SampledSet domain,
                                     SampledSet range,
                                     MathType rangeType,
                                     CoordinateSystem rangeCoordinateSystem)
                              throws VisADException,
                                     RemoteException

Creates a FlatField from a domain SampledSet, a range SampledSet, and a CoordinateSystem for the range. This method should, perhaps, become a method in visad.Set or a constructor in FlatField.

Parameters:

domain - The domain SampledSet.

range - The range SampledSet.

rangeType - The MathType of the range for the returned FlatField.

rangeCoordinateSystem - The CoordinateSystem for the range of the returned FlatField. May be null.

Returns:

The SampledSet promoted to a FlatField. The MathType of the domain will be the RealTupleType of the set (i.e. ((SetType)set.getType()).getDomain().

Throws:

VisADException - Couldn't create necessary VisAD object.

RemoteException - Java RMI failure.

main

public static void main(String[] args)
                 throws VisADException,
                        RemoteException

Tests this class.

Parameters:

args - Ignored.

Throws:

VisADException - if a core VisAD failure occurs.

RemoteException - if a Java RMI failure occurs.